Printing plate mounting



H. J. WARWICK PRINTING PLATE MOUNTING July 10, 1934.

Filed July 1, 1651 2 Sheets-Sheet l v gmmtov July 10, 1934. H. J.WARWICK PRINTING PLATE MOUNTING 2 Sheets-Sheet 2 Filed July 1. 1931Patented July 10, 1934 UNITED STATES PRHNTKNG PLATE MOUNTING HowardJames Warwick, Cleveland, Ohio, as-

signor to Multigraph Company, Wilmington, Del., a corporation ofDelaware Application July 1, 1931', Serial No. 548,078

9 Claims.

This invention relates to means for attaching printing plates tocylinders, and is more particularly concerned with the mounting of aplate of considerable thickness, as, for instance, in an electrotype. Anobject of the invention is to provide means for holding such electrotypedown tightly on the drum throughout its entire arcuate extent.

Considerable difficulty has been experienced in mounting electrotypessnugly on drums, especial- 1y where the electrotype extends for morethan a semi-circumference, and my invention is very applicable toelectrotypes of that character which are adapted to be slipped endwiseover the drum when removed from its shaft.

Another object of the invention is to provide means for retaining theelectrotype in its proper arcuate shape when removed from the drum, so'that it will not be sprung during storage.

I accomplish the desired result by permanently securing to theelectrotype thin sheet metal straps, the ends of which are provided withtensioning means. Preferably two of these straps are employed, seatingin rabbets at the extreme ends of the electrotype and permanentlysecured thereto by solder passing through holes in the straps anduniting with the electrotype base. Such a construction provides theelectrotype with permanent fastening means, which, when the electrotypeis 7 not in use, may hold it in a partly cylindrical form just slightlylarger in diameter than the drum;

then, when it is desired to use the electrotype itmay be slipped endwiseonto a drum having a suitable recess to receive the tensioning means;and then, by tightening the tensioning means, one

clamps the electrotype rigidly to the drum, so that it operates as aunit therewith.

My invention is illustrated in the drawings hereof and is hereinaftermore fully described, and its essential novel features are summarized inthe claims.

In the drawings, Fig. 1 is a vertical section through a rotary printingmachine equipped with my plate mounting; Fig. 2 is a plan of the platecylinder of the machine, with the plate mounted thereon; Fig. 3 is anenlarged cross section through the plate at its tensioning device, asindicated by the line 3-3 on Fig. 2, mounted on a jig roll; Fig. 4 is aperspective of the plate with its holding I means; Fig. 5 is aperspective of the fastening strap and its tensioning device, detached;Fig. 6 is a detail in section showing a portion of a plate cylinder, anelectrotype and the fastening strap.

4 Referring first to Fig. 1, 10 indicates the vertical 5&- frame plateof a printing machine; 11 a horizontal threaded stud 42 has a flattenedhead 43 lying shaft mounted therein and carrying the plate cylinderhereinafter described; 12 an inking system for inking the plate, and 13a rotaryv platen to coact with the plate and print on paper suitably fedbetween them.

The plate cylinder or drum, designated 20, comprises, as shown, a hollowshell extending for something less than a complete circumference anddisc-like end members 21 having hubs 22 which are splined on the shaft11. The omitted portion of the drum shell provides a recess out of theprinting region for the tensioning devices of the plate mounting.

Thirty (30) indicates the printing plate which is shown as anelectrotype having an arcuate extent considerably more than asemi-circumference, but less than a complete circumference. At thearcuate edges of this electrotype beyond the printing surface'ar'eformed rabbets 31. The electrotype body is made as usual with a base ofcomparatively soft metal of considerable thickness and a thin facing 32of different metal, as, for instance, copper, illustrated in theexaggerated view, Fig. 6.

The fastening straps, designated 40, are thin sheet metal members,preferably steel, having a width and height preferably less than thewidth and depth of the rabbet, respectively. The straps thus occupythese rabbets and are well below the printing surface.. Two ends of eachstrap are bent inwardly, as at 41, to project toward each other'inaplane, and these ends are secured together by an adjustable tensioningdevice, which I will now describe.

As shown, in the drawings, the tensioning device comprises a turnbucklehaving an externally threaded stud secured to one end of the strap, andan internally threaded sleeve swivelly connected to the other end of thestrap. The

against the underside of the strap to which it is rigidly secured by twoor more rivets 44 passing through the head and strap and preferablycountersunk in each of them. A suitable block 45 is similarly secured bycountersunk rivets 46 to the other end of the strap. In the free edge Itis a feature of my invention to make the llll straps a permanent part ofthe plate so that they may not only hold it in place on the drum when itis mounted, but may retain it against distortion when it is stored. Toeffect this, I desire to solder the straps directly to the electrotype,and I accomplish this by making a series of openings 51 through thestraps, and corresponding openings through the electrotype facing in therabbets, and passing solder into the openings to unite the straps to theelectrotype base.

I find a very convenient method of procedure is to mount the electrotypeon a suitable jig roll having a diameter corresponding to the printingdrum, as, for instance, the jig roll B in Fig. 3. With the electrotypeon said roll, the straps are put in place, and the turnbuckles tightenedto clamp the electrotype in exactly the same position it is to have onthe drum. Now I pass a drill, indicated as A in Fig. 3, successivelythrough the openings 51 to drill through the copper facing 32 of theelectrotype, and then I pour molten solder 52 through the openings 51.This solder passing through the copper facing 32 autogenously uniteswith the base of the electrotype, which is a metal somewhat similar tothe solder. The soldering studs not only pass through the steel band,but slightly spread over the top thereof, as shown in Figs. 3 and 6, andthus firmly unite the steel band to the electrotype.

An electrotype equipped with my steel bands having the tensioningdevices as shown in Fig. 4, constitutes a unitary printing member whichmay be readily stored in a suitable container with theelectrotype onlyvery slightly larger in internal diameter than the external diameter ofthe printing drum; then, whenever it is desired to use the electrotype,it is slipped endwise over the drum, the tensioning devices occupyingthe recesses of the drum, and rotation of the turnbuckle sleeves effectsa tight clamping of the electrotype on the drum. By this means, I nevervary the curvature of the electrotype an appreciable amount and theaccurate printing surface thereof is maintained in perfect condition.

I claim:

1. The combination of a printing plate, a band having an intermediateregion thereof permanently attached to the plate, and means for drawingtogether the free ends of the band.

:2. The combination of an arcuate printing plate having a recess, a bandlying in the recess, means for permanently attaching the band to thebase portion of the plate beneath it, and means for drawing on therespective ends of the band.

3. The combination of an arcuate printing plate having recesses adjacentits ends, a pair of metal bands lying in the recesses and having freeends, means for permanently attaching the bodies of the bands to theprinting plate, and turnbuckles connecting free ends of the bands.

4. The combination of a printing plate, a band overlying the same andhaving openings through it, and solder passing through the openings andunited to the plate.

5. The combination of an electrotype, a band extending across the same,openings through the band, registering openings through the facing metalof the electrotype, and solder occupying the openings of the band and ofsaid facing and being autogenously united with the base of theelectrotype.

6. The combination of an arcuate electrotype having rabbets at itsedges, a pair of steel bands occupying the rabbets and extending a lessradial height than the plate, openings through the bands, solder passingthrough the openingsand through the electrotype facing to the base ofthe electrotype at the rabbets, and turnbuckles connecting the free endsof the bands.

'7. A plate mounting, comprising the combination with a plate, of astrap having free ends, a threaded stud permanently secured to the onefree end, a block permanently secured to the other free end, and aninternally threaded sleeve swiveled to said block.

8. The combination of a flat metal band for a plate mounting, a threadedstud having a flattened end riveted to the band adjacent one endthereof, a block riveted to the band adjacent the other end, a pincarried by said block and having a head at its far end, and aninternally threaded sleeve having a bore receiving the head and aconstricted end embracing the pin beyond the head, said sleeve beinginternally threaded from its other'end to receive the threaded stud.

9. The combination of an arcuate printing plate, an arcuate bandextending for more than a semi-circle and having its end portions freeand its intermediate region permanently attached to the plate, and meansfor drawing together the free ends of the band.

' HOWARD JAMES WARWICK.

